Core-shell Ni_3Fe-based nanocomposites for the oxygen evolution reaction

摘要

To deal with energy and environmental issues, it is necessary to exploit efficient and stable electrocatalysts for the generation of clean hydrogen. Herein, we describe the synthesis of bimetallic Fe/Ni alloy encapsulated by amorphous carbon shells via a facile annealing strategy for electrocatalytic oxygen evolution reaction (OER). The ferric nickel tartrate annealed at 800 degrees C (Ni3Fe1Ox@C-800) exhibits a low OER overpotential of 264 mV at 10 mA cm-2 and good stability in alkaline media. Compared with monometallic counterpart, bimetallic Ni3Fe-based nanocomposites show lower OER barrier (ca. 324 kJ mol-1) due to a cooperation mechanism between Ni and Fe sites in promoting electrocatalytic water oxidation. Compared with those annealed at other temperatures, the enhanced OER performance of Ni3Fe1Ox@C-800 can be ascribed to the large electrochemical surface area for exposing more active sites, smaller charge transfer, and better intrinsic activity of Ni3Febased sites. (c) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.